Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and a rotor. The rotor typically includes a rotatable hub having one or more rotor blades attached thereto. A pitch bearing is typically configured operably between the hub and the rotor blade to allow for rotation about a pitch axis. The rotor blades capture kinetic energy of wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a main rotor shaft coupled to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
With certain conventional configurations, the rotor shaft is connected to the gearbox via a shrink fit coupling. Certain maintenance procedures, however, require separation of the rotor shaft from the gearbox. During this process, material can be removed and/or deposited on to the rotor shaft at surfaces where the rotor shaft mates with the gearbox, which requires resurfacing of the rotor main shaft to ensure that the rotor shaft is round, concentric to its original rotational axis, and free of defects for a proper shrink fit with the gearbox prior to placing the wind turbine back into operation. With conventional practices, this resurfacing procedure requires removal of the rotor shaft from the drive train (e.g., from the rotor and the gearbox) with a large crane brought to the wind turbine and subsequent off-site machining at significant costs and down time.
Thus, an improved system and method for resurfacing the main rotor shaft of a wind turbine without the necessity of removing the rotor shaft from the drive train (and nacelle) would be desired in the industry.